252 A HISTOEY OF EECENT CEUSTACEA 



tarda has the apex of the telson cleft instead of truncate. 

 Pasiplicea iJrinceps (S. I. Smith), 1884, obtained from a 

 depth of 1,342 fathoms in the North Atlantic, is much 

 larger than the type-species, since it attains a length of 

 between eight and nine inches. The apex of the telson is 

 cleft. 



Leptochela, Stimpson, 1860, is distinguished by having 

 a short one-jointed mandibular ' palp,' and the second 

 maxillipeds not pediform as in Pasiphma, but with the last 

 joint armed with long spines or hairs. The species are 

 not large, Leptocliela robusta, Stimpson, being only an inch 

 long, and his Leptocliela gracilis and Spence Bate's Lepto- 

 cliela serratorhita being still smaller. 



ParapasiplioJe^ S. I. Smith, 1884, has a very small and 

 slender mandibular ' palp,' composed of two nearly equal 

 joints. In Orpliania tenuimdna^ Spence Bate, these organs 

 were not examined, the specimen on which the genus and 

 species were founded being ' unique and not very perfect.' 



Family 10. — Oodeopidce. 



The carapace is short, produced to a long horizontal 

 rostrum. The eye-stalks are short, the eyes large. The 

 mandibles are w^ithout ' palp ; ' the third maxillipeds long, 

 slender, and pediform. The first pair of trunk-legs are 

 chelate or subchelate and larger than the second, which 

 are simple. 



This family was formed for a single genus, but may 

 perhaps receive a second. 



Oodeopus, Spence Bate, 1888, starts with seven species, 

 but as they are all founded on immature auimals, their 

 actual characters remain vague, and with them those of 

 the genus and family. The generic character makes the 

 ' first pair of pereiopoda large and chelate,' but a following 

 observation states that the most advanced specimen in the 

 collection ' shows a tendency to develop the first pair of 

 pereiopoda into a chela in the adult stage. All the other 

 specimens exhibit them in the simple form,' which Spence 

 Bate no doubt rightly takes to be a still more immature 



